coronavirus pandemic
新冠肺炎 新型コロナウイルス感染症 新型コロナウイルス コロナウイルス 武漢肺炎 COVID-19 コロナ禍 SARS‐CoV‐2
An image referencing the late 2019 and onward outbreak and pandemic of Coronavirus Disease 2019 (COVID-19).
Some examples include Danbooru post #3833846 (references the shortage of daily necessities due to panic buying), Danbooru post #3838197 (Closure of Comiket due to COVID-19), or Danbooru post #3819444 (Giuseppe Conte's speech in early March 2020).
Not every post with someone wearing a mouth mask should be tagged with this. The commentary, post, or source tags should make some reference to it.